System of distribution and control.



R. E. HELLMUNmj SYSTEM or DISTRIBUTION AND cou'mor. Arrucmou miq FEB.19,. 1914.

Patented A riso, 1918.

ATTORNEY 1,264,298. a npplieation fi led Febrnaryw, 19 n Serial No.19,737.

ITED srnrnsgrgrnnr orFIon Y BUDOLF n. ,HELLMUND, or PITTSBURGH,PENNSYLVANIA, ASSIGNOR TO wnsrmee I-IOUSE ELECTRIC AND'MA NUFAGTURINGCOMPANY, A CORPORATION OF PENNSYL- value.

To all whom it may concern 5 Be it 'known thatI, "RUnoLr E. I-In Ln-MUND, a subject of, the German Empire, and a resident of Pittsburgh, inthe'county of Allegheny and State'of Pennsylvania, have invented a newand useful Improvement in Systemsfof Distribution andgControl, of whichthe following is a specification.

My invention relates to systems of alter.- nating current distributionand control, and it has special reference to the control of polyphaseinduction 'niotors which are adapted toreceivefenergy from asingleagency of a phase'converter.

One of the objectsof my'inven'tion, is to provide a system of the aboveindicated character in which; the advantages of the construction andoperation of a single-phase distributing system may be combined withphase distributing system through the 'those of polphase'inductionmotors.

Another 0 v ject of my invention is to pro-' vide a phase converter foroperating apolyphase Induction motor from a single-phase 25 "voltage andphase 'position'cf the energy sourcelof energy, and means varying thesupplied to-the" driving with load conditions.

A further object of myinvention is to provide meansassociate'd with aphase conmotor in accordance verter "for compensating for the reactiveand ohmic drop and the phase displacement of the secondary convertervoltage under load conditions.

'A still further object of my invention is to provide a phase converterhaving a plurality ofseparate and' independent windings of differentnumbers of turns, and to providemeans for varying the relative number ofturns and the location of one of the windings for adjusting the amountand phase position of the delivered voltage. I p When phase convertersare employed, they "usually embody a plurality of separate andlike'windings which are disposed in electromagnetic quadraturerelatlonship, whereby a voltage at substantially 90 tothe sourceparatus, when a "load is thrown on the'converter, there is a materialreduction in the delivered voltage by reason of the reactive SYSTEM or,DISTRIBUTION AND ooiv'rnon vSpeeiiication,of lfletters l atent. PatentedAprQ30, 1918- of turns thereof. Moreover, the adjusting means-referredto, are so located With re- "spect to the secondary winding thatithemeat-loner the active turns there rmay actually be shifted forward orbackward as desired Thus, the voltage drop and the for-with facility.

Intheaccompanying drawing, Figure '1 under load conditions,maybe-compensated is a diagrammatic view-of a system of distrlbution andcontrol embodying my Inven- -t1on, and Flg; 2 1s a vector diagramshowing the relationship of certainof'thephase converter voltages underpredetermlned conditions. 1

shown comprises a single-phase supply circuit Or source of energy 1, atransforming device 2, a phase converter 3,'"a polyphase induction motor4 and a liquid rheostat 5.

The supply circuit 1 may constitute a trolley conductor whichis; adaptedto supply alternating-current energyto a primary winding 8 of thetransforming device 2 which is provided with a secondary'windphasedistortion of the secondary energy,

Referring to I the drawing, the 'systeniing 9 having suitableconnections to the phase converter3 and the polyphase induction motor 4,as hereinafter set forth. 9

The phase converter 3 preferably comprises a dynamo-electricmachineofthc induction motor'typehaving a squirrel cagef i rotor 10although it may be of wound rotor type. A plurality of windings '11,12,13 and 14 are associated with the stationary portion of the machine,and, the windings lliand-l2 are oppositely disposed and connectedtogether across the secondary winding 9 of the transformer 2andare' thusex cited in phase with the transformer voltage.

I The windings l3 and 14: constitute thels'econdary converter windingsand are oppositely disposed and in quadrature to theprimary-windings'll' and 12, being electro -mag- The windings 11 and 12constitute the primary or exciting windings of the converter.

netically related thereto, although otherwise separate and independenttherefrom. The

windings l3 and 1 1 are connected in series across one of the windings16 of the 1nduc-' 7 tion motor 4 and are respectively provided withswitching devices lS and 19, and 20 and 21 which are located at therespective ends thereof for the purpose of adjusting the number of turnsand the position of the active turns of said windings. The wind ings 13'and 14: are diagrammatically shown and, in the actual construction, mayassume any one of a variety of forms, such, for example, as a portion ofone of the stator windlngs shown in U. S. Patent 1,170,657, issued totheWestinghouse Electric &Manufactur ing Company, February 8,1916, on anapplication filed by F.- W. Meyer. The essential feature ofsaidwi-ndings is that they be of the distributed type so that by addingactive turns at one end thereof and eliminating active turns in theother end thereof, the

axes of activity of the field produced thereby may be shifted and bysimultaneously increasing or decreasing the numberof active .turns ateach end of the winding, the magnitude of the field produced thereby maybe altered. A larger number of turns is provided upon the secondarywindings 13 and 14 than upon the primary windings 1 1 and .fore, besubstantially in quadrature with the energy of the transformer 2, whichis adapted to deliver energy to the other primary winding 23of the motor4. i

The secondary windings 25 and 26 of the motor 4 are connected to aplurality of electrodes 28 which are suspended within atank 29 havingsuitable inlet and outlet valves (not shown) for the admission anddischarge of an electrolyte. The tank 29 and its electrodes 28constitute an adjustable liquidrheostat and are included in the circuitsof the secondary windings 25 and 26 of the induction motor for thepurpose of controlling the speed. of the motor.

Under no-load conditions, the relationship .of the transformer voltageandthe voltage -of thecphase converter secondary windings 13 and 1 1 isindicated by lines E 'and E in the vector diagram shown in Fig. 2. Thevoltages supplied to the several phase windings of the induction motor 4are, therefore, equal and at 90 to each other. However, as load isplaced upon the motor 41, there is a reduction of voltage and a phasedistortion thereof in the converter secondary windings,

and the voltage delivered to the induction motor winding 16 is thenindicated by line E Under these conditions, there is an unbalancedcondition of operation which is undesirable. a

In order to compensate for unbalanced load conditions, the switchingdevices 18,19, 20 and 21 may be adjusted to increase the number ofactive turns of the secondary converter windings 13 and 14 in order toraise the delivered voltage to the desired amount, while thedisplacement of phase position may be compensated for byjsuitableadjustments of said. switching devices in one direc tion' or; the other,according to, conditions, whereby'the location of the active turns ofthe windingsli and 14 may actually be shifted with respect to theprimary e'x'clting windings 11 and 12.

Having'thus increased the converter secondary voltage and correctedrmits phase displacement, balanced load conditions" are obtained andsatisfactory operationmay be secured. It is evident that any loadconditions maybe compensated for in the manner hereinbefore described. 7r

' -Al thought I have set forth my invention, for illustrative purposes,in connection. with a phase converter and motor of the two phase type,it is equally applicable to three phase machines of suitable design.Moreover,

.. other means for accomplishingthe same results may beemployed, and Ido not wish to be restrictedto the specific connections and arrangementsof parts set forth, and desire that only such limitations shall beimposed as are indicated in claims.

I claim as my invention: u e 1. In a phase converter of thedynamoelectric type, the combination with a primary winding, of atertiary winding, one

the appended of said windings being of the progressive distributed typeand split into two portions,

a circuit connected to the respective portions I and secondary windings,of a tertiary winding of the progressive distributed type, a

load circuit, connections from'said tertiary winding to said loadcircuit, means forad: justing the points of attachment of said loadcircuit to said tertiary winding, and means for eliminating. a portionofthe turns'of said tertiary winding intermediate the points'cofattachment-10f said load circuit thereto, said last named meansbeinga'djustable so that both the number and the. posi- 171011 of sa1deliminated turns may be varied.

8. In a phase-converter of the dynamoelectric type, the combination withprimary and secondary windings, of a tertiary winding of the progressivedistributed type divided into two portions, means for connecting a pointadjacent a terminal of one of said portions to a point adjacent aterminal of the other of said portions, said points of connection eachbeing adjustable, a load circuit, and means for connecting said loadcircuit to points adjacent the remaining terminals of said tertiarywinding, respectively, said last-named points of connection also beingadjustable. 7

4. In a phase-converter, the combination with primary and secondarywindings, of an "even number of progressively distributed tertiarywindings disposed thereon to produce spaced tertiary poles, a loadcircuit,

connections from said load circuit to terminals of certain'of saidtertiary windings, respectively, and interconnections between theremaining terminals of said tertiary windings respectively, all of saidterminals being adjustable, whereby the phase and magnitude of theinduced tertiary voltage may be varied.

In testimony whereof, I have hereunto B. B. HINEs, M. C. MERZ.

copies 01 this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. 0.

